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1.
Research topics and research communities are not disconnected from each other: communities and topics are interwoven and co-evolving. Yet, scientometric evaluations of topics and communities have been conducted independently and synchronically, with researchers often relying on homogeneous unit of analysis, such as authors, journals, institutions, or topics. Therefore, new methods are warranted that examine the dynamic relationship between topics and communities. This paper examines how research topics are mixed and matched in evolving research communities by using a hybrid approach which integrates both topic identification and community detection techniques. Using a data set on information retrieval (IR) publications, two layers of enriched information are constructed and contrasted: one is the communities detected through the topology of coauthorship network and the other is the topics of the communities detected through the topic model. We find evidence to support the assumption that IR communities and topics are interwoven and co-evolving, and topics can be used to understand the dynamics of community structures. We recommend the use of the hybrid approach to study the dynamic interactions of topics and communities.  相似文献   

2.
In this study, MatrixSim, a new method for detecting the evolution paths of research topics based on matrix similarity, was proposed. In the analysis of research topic evolution with the help of co-word networks, in contrast to traditional methods of topic evolution path detection, such as cosine similarity and edge similarity, MatrixSim is based on the local community structure of topic communities in co-word networks and considers the similarity of research topics in both nodes and edges, that is, words and inter-word relations. Using the library and information science field as an example, two sets of experiments were designed for topic similarity detection and subject-specific research topic evolution analysis to evaluate and verify the performance of MatrixSim in detecting the evolution paths of research topics and its validity and feasibility in research topic evolution analysis. The results confirm that MatrixSim performs well in detecting the evolution paths of research topics. It can correlate important research topics, help describe the research development process in scientific fields, reveal the internal evolutionary features of research topics, and thus discover and track the research frontiers in scientific fields. This study provides significant methodological support for researchers conducting prospective research activities.  相似文献   

3.
Various factors are believed to govern the selection of references in citation networks, but a precise, quantitative determination of their importance has remained elusive. In this paper, we show that three factors can account for the referencing pattern of citation networks for two topics, namely “graphenes” and “complex networks”, thus allowing one to reproduce the topological features of the networks built with papers being the nodes and the edges established by citations. The most relevant factor was content similarity, while the other two – in-degree (i.e. citation counts) and age of publication – had varying importance depending on the topic studied. This dependence indicates that additional factors could play a role. Indeed, by intuition one should expect the reputation (or visibility) of authors and/or institutions to affect the referencing pattern, and this is only indirectly considered via the in-degree that should correlate with such reputation. Because information on reputation is not readily available, we simulated its effect on artificial citation networks considering two communities with distinct fitness (visibility) parameters. One community was assumed to have twice the fitness value of the other, which amounts to a double probability for a paper being cited. While the h-index for authors in the community with larger fitness evolved with time with slightly higher values than for the control network (no fitness considered), a drastic effect was noted for the community with smaller fitness.  相似文献   

4.
Dynamic development is an intrinsic characteristic of research topics. To study this, this paper proposes two sets of topic attributes to examine topic dynamic characteristics: topic continuity and topic popularity. Topic continuity comprises six attributes: steady, concentrating, diluting, sporadic, transforming, and emerging topics; topic popularity comprises three attributes: rising, declining, and fluctuating topics. These attributes are applied to a data set on library and information science publications during the past 11 years (2001–2011). Results show that topics on “web information retrieval”, “citation and bibliometrics”, “system and technology”, and “health science” have the highest average popularity; topics on “h-index”, “online communities”, “data preservation”, “social media”, and “web analysis” are increasingly becoming popular in library and information science.  相似文献   

5.
Linked topics in science and technology (LTSTs) can provide new avenues for technological innovation and are a key step in the transition from basic to applied research. This paper proposes a science and technology semantic linkage integration model for discovering LTSTs. Particularly, the integrative model fuses the term co-occurrence networks of basic and applied research, which expands the completeness of topic networks by enhancing the semantic characteristics of these networks. It is found that link prediction can further reinforce the semantic association of topic terms in networks between basic and applied topics. Simple fusion explicitly linked the topic terms, which can be used as automatic seed marking for subsequent link prediction to identify implicit linking of topic terms. Furthermore, an application to the gene-engineered vaccines field depicted that newly predicted implicit relations can effectively identify LTSTs. The results also show that implicit semantic recognition of LTSTs can be enhanced through simple fusion, while the recognition of LTST can be improved through link prediction. Therefore, the proposed model can assist experts to identify LTSTs that cannot be recognized through simple fusion.  相似文献   

6.
基于动态LDA主题模型的内容主题挖掘与演化   总被引:1,自引:0,他引:1  
指出文本内容主题的挖掘和演化研究对于文本建模和分类及推荐效果提升具有重要作用。从分析基于LDA主题模型的文本内容主题挖掘原理入手,针对当前网络环境下的文本内容特点,构建适用于动态文内容本主题挖掘的LDA模型,并通过改进的Gibbs抽样估计提高主题挖掘的准确性,进而从主题相似度和强度两个方面研究内容主题随时间的演化问题。实验表明,所提方法可行且有效,对后续有关文本语义建模和分类研究等具有重要的实践意义。  相似文献   

7.
Topic emergence detection aids in pinpointing prominent topics within a given domain, providing practical insights into all interested parties on where to focus the limited resources. This paper employs the network-based topic evolution approach to overcome limitations in text-based topic evolution, providing prospective topic emergence prediction capabilities by representing emergent topics by their ancestors. A descendant-aware clustering algorithm is proposed to generate non-exhaustive and overlapping clusters, utilizing the pace of collaborations and structural similarities between topics with iterative edge removal and addition processes. Over 100 datasets specific to a research topic were extracted from the Microsoft Academic Graph dataset for the experiments, where the proposed algorithm consistently outperformed existing clustering algorithms in generating clusters with a higher likelihood of being ancestors to an emergent topic up to three years in the future. Regression-based cluster filtering using five structural cluster features and topic cluster qualities showed that the prediction performance can be enhanced by automatically classifying undesirable clusters from previously known data. The results showed that the proposed algorithm can enhance topic emergence predictions on a wide range of research domains regardless of their maturities, popularities, and magnitudes without having access to the data in the predicted year, paving a road to prospective predictions on emergent topics.  相似文献   

8.
社交媒体虚假健康信息特征识别   总被引:3,自引:2,他引:1  
[目的/意义]识别社交媒体虚假健康信息特征,构建社交媒体虚假健康信息特征清单,以期为社交媒体虚假健康信息特征的测度提供一定理论支撑,也为用户和社交媒体平台判别虚假健康信息提供有益参考.[方法/过程]采集1 004条社交媒体健康数据,利用程序化编码抽取社交媒体虚假健康信息的关键特征,运用卡方检验和方差分析揭示社交媒体虚假...  相似文献   

9.
[目的/意义] 针对单学科和双学科主题发现方法无法挖掘现有交叉文献中主题演化来源的问题,提出面向跨学科的主题发现方法,为跨学科发展和合作提供依据。[方法/过程] 首先在动物资源与育种领域期刊文献数据中选取已经出现交叉现象的两个基础学科文献及其交叉文献,使用改进的主题相关分析方法,提取共同主题和各自的独立主题;然后利用相关性测度方法量化不同学科独立主题的相关性;最后对共同主题和相似性较高的独立主题进行具体分析。[结果/结论] 在动物资源与育种领域的农学生殖生物学、兽医学以及其交叉文献上进行实验验证,结果表明所提出的方法能够有效发现交叉主题的学科出处。  相似文献   

10.
[目的/意义] 基于主题关联相似度揭示主题汇聚及变异过程,识别学科交叉主题及交叉模式,归纳学科主题的演化趋势及演化路径模式。[方法/过程] 获取情报学学科科研论文的高频主题词,构造主题词共词矩阵,利用网络社区演化分析工具生成学科主题演化网络图,结合指标数据对学科主题演化过程进行分析。[结果/结论] 总体上看,情报学学科的研究主题虽然在反复地变化,但核心主题一直存在;扩张、收缩和合并是研究主题最普遍的变化态势,分裂现象较少,产生和消亡现象存在;有3条特定社区演化轨迹清晰地贯穿始终,活跃度相对稳定,反映了3类核心研究主题;3类核心研究主题的演化路径呈现出升华吸纳、共融迭新和辐射推进3种演化模式。研究结果显示,基于主题关联学科主题演化路径的多模式识别方法既能从宏观层面呈现学科主题演化形式,也能从微观层面分析学科主题交叉模式,结合二者可揭示学科主题的继承或创新,预测学科交叉主题的发展方向。  相似文献   

11.
12.
[目的/意义]探测高血压医学文献的主题和演化趋势,对发现高血压领域的研究热点和前沿,理解高血压领域概况和促进专家之间的知识交流具有重要意义。[方法/过程]以PubMed数据库下载的26 717篇与高血压相关的文献题录数据作为研究对象,抽取高频主题词构造共现矩阵,同时采用社会网络分析(SNA)和狄利克雷多项回归(DMR)主题模型从中观、微观层面探测高血压医学文献的主题分布和演化趋势;比较这两种方法的关联和异同点。[结果/结论]研究发现,高血压医学文献主要集中在危险因素、研究方法、基本要素、诊断治疗和动物实验这5个研究主题,主题的相对分布比率随着时间变化而不断改变。利用SNA方法获取的主题词更加具体和明确,而DMR方法获取的主题词更加宽泛,但在探索各个主题的演化趋势方面比较有优势。  相似文献   

13.
Topic extraction presents challenges for the bibliometric community, and its performance still depends on human intervention and its practical areas. This paper proposes a novel kernel k-means clustering method incorporated with a word embedding model to create a solution that effectively extracts topics from bibliometric data. The experimental results of a comparison of this method with four clustering baselines (i.e., k-means, fuzzy c-means, principal component analysis, and topic models) on two bibliometric datasets demonstrate its effectiveness across either a relatively broad range of disciplines or a given domain. An empirical study on bibliometric topic extraction from articles published by three top-tier bibliometric journals between 2000 and 2017, supported by expert knowledge-based evaluations, provides supplemental evidence of the method’s ability on topic extraction. Additionally, this empirical analysis reveals insights into both overlapping and diverse research interests among the three journals that would benefit journal publishers, editorial boards, and research communities.  相似文献   

14.
[目的/意义]作为科学学预测的重要组成部分,学科主题热度预测旨在揭示学术前沿和发展趋势,辅助学者发现前沿选题,支持科研管理机构科学立项。[研究设计/方法]提出基于期刊影响因子的学科主题热度计算指标(TP-JIF),构建基于LSTM神经网络的学科主题热度预测模型(TPP-LSTM),并以LIS领域数据为例,通过时间切片的形式抽取、计算学科主题的热度序列,检验不同长度时间序列下模型的各项误差。[结论/发现]相对于RBF-SVM、Linear-SVM、KNN、Naive Bayesian等模型,TPP-LSTM预测模型可有效表征学科主题热度时间序列的特性,当时间序列长度为4年时预测效果相对较好。[创新/价值]提出的基于期刊影响因子的学科主题热度计算指标,能够有效刻画不同学术刊物对学科影响的差异,规避了单纯依据频率计算热度的弊端;构建的学科主题热度预测模型,有效表征了学科主题的时间序列变化规律,减小了各项预测误差,预测效果较好。  相似文献   

15.
Emerging research topic detection can benefit the research foundations and policy-makers. With the long-term and recent interest in detecting emerging research topics, various approaches are proposed in the literature. Though, there is still a lack of well-established linkages between the clear conceptual definition of emerging research topics and the proposed indicators for operationalization. This work follows the definition by Wang (2018), and several machine learning models are together used to detect and foresight the emerging research topics. Finally, experimental results on gene editing dataset discover three emerging research topics, which make clear that it is feasible to identify emerging research topics with our framework.  相似文献   

16.
认知情感视角下青少年信息查询行为研究进展述评   总被引:1,自引:0,他引:1  
张敏  鲍红琼 《图书情报工作》2016,60(14):142-148
[目的/意义]系统归纳和总结青少年信息查询行为中认知和情感因素的研究现状,指出研究存在的不足和未来发展方向,以期对进一步研究提供借鉴和参考。[方法/过程]通过主题检索和引文追溯收集相关研究文献,将检索到的文献从认知和情感两方面,归纳研究主题和现状。[结果/结论]当前研究主题主要涉及青少年信息查询中的认知表现,认知行为过程模型、认知风格、元认知、认知权威以及不同认知风格和情感类型对青少年查询行为、查询策略、查询结果质量的影响等。未来研究应立足多元复杂社会网络和技术使用情境,加强青少年信息查询过程中的认知情感干预调节和指导研究,从更细微动态的维度剖析认知情感特征和作用机制。  相似文献   

17.
生命科学近五年论文引文情况分析   总被引:1,自引:1,他引:0  
基于网络描述的复杂社会结构能够更好地展示网络中个体的联系特征,由此产生的复杂网络理论已经被广泛应用到社会科学的各个领域。近年来,除了对网络结构所具有的小世界、幂率分布等静态特性的分析外,大量研究开始关注网络结构中个体的组织特征。由这些个体组成的子图中,个体间有着更高的连接特征,而与其他子单元间的个体连接则相对稀疏。这种子单元通常被称为社团。社团发现及分析对研究网络的组织结构和社会特征有着重要意义。将社团发现方法应用到文献分析中,可以得到各学科领域的特征及关联关系。文章利用生命科学领域最近五年间的期-{iJ论文文摘记录,构造了两种引文网络。直接的引用网络和间接的论文耦合网络。对这两个网络基本属性的分析有助于了解生命科学领域发展的现状。此外,文章还使用了两种基于耦合网络的社团分析方法,重点分析了最近五年间生命科学领域的学科分类、关联特征以及随时间的演化情况,以助于理解整个生命科学领域的学科结构。  相似文献   

18.
[目的/意义]研究前沿的准确判断是国家宏观层面的战略需求,文献计量学作为一种定量研究方法广泛应用于科学主题探测和研究前沿识别中。[方法/过程]梳理研究前沿主题探测的发展历程和方法模型,引入全域微观模型的概念,详细介绍SciVal模块采用的主题创建方法,包括直接引用文献聚类、关键词主题命名和研究前沿遴选的主题显著性算法,并对SciVal创建的9.6万个主题和遴选出的前1%的研究前沿主题的特征进行实证分析。[结果/结论]全域微观模型可以同时一次识别整个科学领域的所有主题,但不同学科在研究前沿上表现存在差异,不能把主题显著性简单等同为重要性;主题论文数量与主题排名之间存在中度相关性;自动抽取的关键词术语从学科领域层和独特性上命名和描述主题;石墨烯相关前沿主题的演变趋势分析可以用于发现关键节点和新兴主题。  相似文献   

19.
周洁 《出版科学》2011,(4):91-95
对《时代》周刊和《三联生活周刊》2010年所有封面故事的主题类别进行分类统计,并从选题类型、选题分布、特刊选题和封面标题四个方面分析两刊的选题情况,发现两刊除了同样关注社会类选题外,在选题侧重点、选题视野、对读者的引导和塑造以及标题的制定等方面都存在较大差别。  相似文献   

20.
从社区到社会网络——一种互联网研究视野与方法的拓展   总被引:9,自引:0,他引:9  
随着互联网技术的发展,传统的BBS等虚拟社区的影响有所减弱,而由SNS、即时通信、博客等应用构建的新兴社区的影响正在上升,这些新的应用也促进了人们的社会网络的形成与拓展。借鉴社会学的社会网络理论来研究这些新的应用及其影响,是十分必要的。人们从传统虚拟社区向以自我为中心的社会网络的迁移,体现了网络使用者从社会归属需求向社会资本需求的升级,而印象管理、自我表达、情绪调节、社会交往、社会分享、社会参与等其他层面需求则与社会资本需求相辅相成。互联网上的社会网络对于个体的影响,目前主要在两个方面表现出来:一方面是一对一的互动对个体的态度、行为的影响(这些影响可以从社会心理学的一些传统理论中得到解释),而这种一对一的影响还可能通过社会网络来传递,从而形成一种社会性影响;另一方面是社会网络的结构对个体所施加的影响,例如,社会网络中的权力关系的影响、社会网络中的派系的影响等。  相似文献   

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